From 7069072c10f54de136613947a5b82f504e5f8478 Mon Sep 17 00:00:00 2001
From: "maxime@cerno.tech" <maxime@cerno.tech>
Date: Thu, 20 Oct 2022 11:12:09 +0200
Subject: [PATCH] firmware: raspberrypi: Introduce
 rpi_firmware_find_node()

A significant number of RaspberryPi drivers using the firmware don't
have a phandle to it, so end up scanning the device tree to find a node
with the firmware compatible.

That code is duplicated everywhere, so let's introduce a helper instead.

Link: https://lore.kernel.org/r/20220815-rpi-fix-4k-60-v4-1-a1b40526df3e@cerno.tech
Signed-off-by: Maxime Ripard <maxime@cerno.tech>
---
 drivers/firmware/raspberrypi.c             | 18 ++++++++++++------
 include/soc/bcm2835/raspberrypi-firmware.h |  7 +++++++
 2 files changed, 19 insertions(+), 6 deletions(-)

--- a/drivers/firmware/raspberrypi.c
+++ b/drivers/firmware/raspberrypi.c
@@ -429,6 +429,18 @@ static int rpi_firmware_remove(struct pl
 	return 0;
 }
 
+static const struct of_device_id rpi_firmware_of_match[] = {
+	{ .compatible = "raspberrypi,bcm2835-firmware", },
+	{},
+};
+MODULE_DEVICE_TABLE(of, rpi_firmware_of_match);
+
+struct device_node *rpi_firmware_find_node(void)
+{
+	return of_find_matching_node(NULL, rpi_firmware_of_match);
+}
+EXPORT_SYMBOL_GPL(rpi_firmware_find_node);
+
 /**
  * rpi_firmware_get - Get pointer to rpi_firmware structure.
  * @firmware_node:    Pointer to the firmware Device Tree node.
@@ -484,12 +496,6 @@ struct rpi_firmware *devm_rpi_firmware_g
 }
 EXPORT_SYMBOL_GPL(devm_rpi_firmware_get);
 
-static const struct of_device_id rpi_firmware_of_match[] = {
-	{ .compatible = "raspberrypi,bcm2835-firmware", },
-	{},
-};
-MODULE_DEVICE_TABLE(of, rpi_firmware_of_match);
-
 static struct platform_driver rpi_firmware_driver = {
 	.driver = {
 		.name = "raspberrypi-firmware",
--- a/include/soc/bcm2835/raspberrypi-firmware.h
+++ b/include/soc/bcm2835/raspberrypi-firmware.h
@@ -168,6 +168,7 @@ int rpi_firmware_property(struct rpi_fir
 int rpi_firmware_property_list(struct rpi_firmware *fw,
 			       void *data, size_t tag_size);
 void rpi_firmware_put(struct rpi_firmware *fw);
+struct device_node *rpi_firmware_find_node(void);
 struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node);
 struct rpi_firmware *devm_rpi_firmware_get(struct device *dev,
 					   struct device_node *firmware_node);
@@ -185,6 +186,12 @@ static inline int rpi_firmware_property_
 }
 
 static inline void rpi_firmware_put(struct rpi_firmware *fw) { }
+
+static inline struct device_node *rpi_firmware_find_node(void)
+{
+	return NULL;
+}
+
 static inline struct rpi_firmware *rpi_firmware_get(struct device_node *firmware_node)
 {
 	return NULL;
